Sensing unit with printed circuit



March 22, 1966 J, LE BRUN, JR

SENSING UNIT WITH PRINTED CIRCUIT g Sheets-Sheet 1 Filed Aug. l0, 1961NOE ENVENTOR. EUGENE J LE BRUN/JR.

March 22, 1966 E. J. LE BRUN, JR

SENSING UNIT WITH PRINTED CIRCUIT z Sheets-Sheet 2 Filed Aug. 10, 1961INVENTOR. EUGENE J LE BRUN,JR.

United States Patent O tion of Delaware Filed Aug. 10, 1961, Ser. No.130,541 12 Claims. (Cl. 235-6111) This invention relates to a cardsensing unit employing printed circuit components and more particularlyto a unit of this type including a plurality of electrically conductivesensing brush elements mounted on a removable support member.

One conventional method of storing information on a card for controllingbusiness machines is the punching of data perforations therein in apredetermined code usually columnwise of the card by the use of suitablecard punching mechanism. In subsequent control by or retrieval of thestored information, the card is moved at high speed through a sensingunit Where the information is taken from the card and utilized fordesired purposes. One type of card sensing unit employs a plurality ofspaced, conductive elements for completing individual eletrical circuitsbetween a common electrically conductive member positioned on one sideof the card and the elements positioned on the opposite side thereof.Conveniently, there have been employed a plurality of flexibleconductive wire or brush elements, one for each column of the card,which brushes are positioned along a line extending across the path ofthe moving card and laterally of the columns thereof to completeindividual electrical circuits depending upon the position of theperforations in each of the columns of the card. In addition to the needfor a large number of individual brush elements or wires in a relativelyconfined space, there is also required a like number of individuallyassociated insulated wires or leads for delivering the electricalcurrent impulses from each of the brush elements to cooperatingelectrical apparatus. Since the data cards are moving at exteremely highspeed, and since the brush elements are relatively delicate, damage toor destruction of the brush elements often occurs during the operationof the sensing unit. Subsequent removal and replacement of theindividual brush elements or the member acting to support all of thebrush elements is achieved only with great difficulty since themultitude of wires or leads are rigidly coupled normally to theindividual brush elements.

It is, therefore, the principal object of this invention to provide animproved card sensing unit of the electrical brush type in which thebrush elements may be readily and easily removed without interferencefrom the individual brush leads connected thereto.

It is a further object of this invention to provide an improved cardsensing unit of the multiple brush element type which is of extremelysimple construction and is readily adapted to structures employingprinted circuitry connections to the individual brush elements.

It is a further object of this invention to provide an improved ca-rdsensing unit of the multiple brush element type in which the danger ofdestruction or damage to the brush elements or to the parts associatedwith the sensing unit, during removal of the brushes from the unit, isgreatly minimized.

Further objects of the invention are: to provide for collective andindividual adjustment of the brushes; to provide positive control of thebrush unit so that it can be safely removed at only one position ofadjustment Without damaging the brushes, the record card or the printedcircuit carrier; to yieldably position a brush carrier so that it Willautomatically break contact of the brushes with the data card to besensed and the printed circuit carrier prior to removal as a unit fromthe machine; and to provide for fool-proof positioning of the brusheswith respect to the data card and the printed circuit carrier afterinsertion of the brush unit into the machine.

Other objects of this invention will be pointed out in the followingdetailed description and claims and illustrated in the accompanyingdrawings which disclose, by way of example, the principle of thisinvention and the best mode which has been contemplated of applying thatprinciple.

In the drawings:

FIG. 1 is a front elevational view of one embodiment of the presentinvention,

FIG. 2 is a plan view of that portion of the machine shown in FIG. 1,

FIG. 3 is a vertical section taken on the line 33 of FIG. 1,

FIG. 4 is an end elevation taken substantially on the line 4-4 of FIG.1,

FIG. 5 is a detail view of the sensing roll adjusting means,

FIG. 6 is a fragmentary section on the line 66 of FIG. 5,

FIG. 7 is a section on the line 77 of FIG. 3,

FIG. 8 is a section on the line 88 of FIG. 3,

FIG. 9 is a section on the line 9-9 of FIG. 5,

FIG. 10 is a view in elevation of one end of a modified form of brushmounting,

FIG. 11 is a vertical section on the line 1111 of FIG. 10, and

FIG. 12 is a detail view of a spring mounting used in the structure ofFIG. 11.

In general, the apparatus of this invention comprises a card sensingunit of the multiple brush element type including an elongatedconductive member connected to a source of electrical potential andadapted to feed or support a moving card. A printed circuit boardcarrying a plurality of spaced, insulated stationary contacts ispositioned adjacent the conductive member carrying the perforated card.Intermediate these members is provided a brush support member includinga plurality of individual, cooperating spaced conductive bl'LlSllelements and support means allowing the brush support member to be movedtoward and away from the elongated conductive member and the printedcircuit contact board, to allow individual electric circuits to becompleted from the conductive member to the individual, associatedprinted circuit board contacts, while facilitating removal of the brushsupport member from the unit.

Referring to the drawings in detail, 10 indicates a part of the body ofa card sensing machine having side brackets 11 to which are boiled orotherwise secured end wing portions 12 connected by an integral barsection 13 constituting a support from which is suspended a sensingbrush holder unit 14. The latter along its upper edge carries channelmembers 16 and 17, FIG. 3, the former having upwardly diverging sidesand constituting a slide fitting into an undercut slot 18 in the bottomof said bar section 13, the sides of the latter of which are embraced bythe sides of the channel 17 which acts as a guide for removal andreplacement, in endwise direction, of the brush holder unit 14.

The bar section 13 also carries a removable panel member 19 to which isfixed by any suitable means a printed circuit card 20 or element,constituting a stationary contact member.

This frame has journalled therein a conductive member in the form of acylinder or roll 21 over which is fed a card 22 containing perforations23 arranged in any the card. While the elongated conductive member 21 isshown as a cylinder, and may be rotatable about its own axis tocorrespond with the movement of the card 22, this member 21 or platenmay take any other desired form, that is, it may be stationary and havea perfectly flat surface over which the card can be fed, the onlyrequirement being that it be electrically conductive to complete anelectrical circuit between its surface and rigid or flexible brushelements 26 carried by the sensing brush holder unit 14.

In this sense. roll 21 is conventionally termed the hot roll and mayalso be referred to herein as a sensing roll. Also, as shown in FIG. 3,there is provided a second identical brush element 27 which makescontact with its associated conductive portion 28 of the printed circuitelement 20 to achieve an electrical circuit passing from the fullyconductive hot roll 21 through the lower brush element 26 and the upperbrush element 27 to the printed circuit contact member 20.

One aspect of the present invention is directed to an improvedarrangement for the supporting means 24 for the individual brushelements 26 and 27, which are moved or rotated out of contact with thehot roll 21 and the printed circuit contact member 20 respectively,facilitating removal of the brush support member 26 from the assemblyfor subsequent replacement or repair of all or any of the brush elementsor of the associated circuitry without in any way affecting the greatnumber of electrical conducting elements or wires normally associatedwith the sensing brush structures of this type.

Referring to FIG. 3, the brush support member or holder unit 24 for theindividual brush elements takes the form, in the preferred embodiment,of an elongated, rectangular carrier rod or bar 29, preferably ofinsulating material and having substantially a cruciform shape in crosssection. Bar 29 has formed on opposing top and bottom surfaces or faces31 and 32 respectively, a number of spaced parallel grooves or slots 33acting to re ceive the upper and lower individual, flexible, conductivebrush elements or wires 27 and 26 respectively. The free ends 34 and 36respectively of these elements extend outwardly beyond the sides of thebar 29 in opposite directions and are beveled to insure maximum contactwith the associated printed circuit stationary contacts 20 and the hotroll 21. In order to insure electrical continuity from one of theflexible brush elements 26 to the oppositely positioned and alignedelement 27, as well as to secure the brush elements within theirrespective slots 33, there is provided a plurality of set screws 37which pass completely through the insulating rod 29 to engage andfrictionally secure the rear portions of the brush elements 26 and 27 intheir slots 33.

In FIG. 3, there is shown a pair of removable brush guides 38 which areconnected to the sides of the rod 29 by screws 39 during the initialmounting stage and have surfaces 41 which abut the inner end of thebrush elements 26 and 27 to accurately position the elementslongitudinally within their respective slots. After the individual brushelements 26 and 27 have been aligned or adjusted they are secured withintheir slots by tightening of screw bolts 37 which are slotted as at 37Ato receive the brushes 26 and 27 (FIG. 8), after which the guides may beremoved. Thus, all of the brushes may be aligned simultaneously or theycan be adjusted individual ly to compensate for wear.

In order to facilitate longitudinal removal of the brush support member24 from the sensing unit, without interference from the associatedstationary contact members and to guard the brushes against damageduring and after removal of the unit, bar 29 may be rotated through alimited number of degrees about its own axis. Referring to FIGS. 1 and3, the elongated rod or support member 29 has affixed at each end acoupling member 40 having flanges which are rigidly secured to theopposite sides of the bar 29. Fixedly attached to each flanged member isa detent arm 43 which in the lowered position (FIG. 3) will preventlongitudinal removal of the unit 14 by engaging the frame, and a centralshaft 44 whose ends extend through suitable apertures formed instationary support brackets 46 at opposite ends of the apparatus, theapertures forming bearing surfaces allowing rotation of the shaft. Atthe right end of the unit, as seen in FIG. 1, there is provided thelaterally directed detent arm or lever 43 which has a bore receiving theend of the shaft 44 and having a set screw or other means to secure thedetent arm 43 on the shaft 44 in any desired position. The shaft 44 isallowed a limited rotation of approximately 20 degrees with the lever 43moving from an inclined position where the brush ends 36 and 34 areprotected within the openings 14B and 148 to a position approximatelyhorizontal to locate brush elements 26 and 27 in contact with theassociated roll 21 and the printed circuit board 20.

To facilitate removal of the brush supporting carrier bar 29, thestationary support bracket members 46 are generally U-shaped inconfiguration with legs 54 being rigidly coupled by suitable set screws60 to longitudinally extending, horizontal support strip members 56 and58. The opposite end of shaft 44 from the detent arm 43 carries a gear62 which meshes with a pinion 64 secured to a stud shaft 63 journalledin a bracket 65, which shaft has secured thereto the collar 66 of ahandwheel 67. The collar has a radially extending pin 68 (FIG. 5)coacting with spaced limit pins 69 on the bracket to define the rotationof the stud shaft and the extent of rotary movement of the detent arm 43by reason of a suitable ratio of operation of the gears 62 and 64. Thestud shaft 63, FIG. 5, is slidable endwise against the resistance of aspring 70 so that locking pins 71 projecting from the-end of a gear hub72 can be withdrawn from holes 73 in the bracket 65 to free thehandwheel 67 for rotation. The position of the pins 71 maintains theproper position of shaft 44 so that the brushes are located in thedesired position, especially when positioned to cause the brushes tomaintain contact between the hot roll 21 and the printed circuit 20.Such means, however, does not prevent the ready removal of the brushsupport member by the simple process of pulling on the handw'neel tofree the pins 71 and rotating the handwheel or swinging the lever 43counterclockwise to rotate shaft 44 from the normal circuit completingposition to the inclined position, at which time, the brush elements 26and 27 will leave their contact surfaces to break the circuits and allowthe brush support 24 to be removed longitudinally from the left as inFIG. 1.

It should be noted that the present invention is most advantageouslyused with stationary contacts of the printed circuit type. The upper endof the panel member 19, FIG. 3, is provided with conventional electricalconnecting means 75 allowing a relatively large number of individualinsulated electrical leads or wires 76 to be connected to a singleelement printed circuit board or member 20 which includes a plurality ofspaced electrical conductive portions or stripes 28 which are aligned atone end with the spaced brush elements 27 and make cooperative contactupon rotation of shaft 44 in the manner specified previously. Inconventional sensing units of this type, each of the individual leads orwires 76 is required to be connected directly to its associated wirebrush element, thus preventing or at least greatly complicating theremoval of any or all of the brush elements. With the greatly simplifiedstructure of the present invention, there is only the requirement of asingle element printed circuit board 20 having a desired configurationallowing individual, spaced conductive portions 28 to be placed incontact with aligned cooperating brush elements positioned on a singlebrush support member which may be rotated or moved to facilitate easyremoval of the brush unit 14, should such removal be necessary.

A second embodiment of the present invention is shown in FIGS. 10, 11and 12 which basically comprises the same elements as in the embodimentsof FIGS. 1 to 9. However, in the embodiment of FIG. 11, there is no needto preliminarily rotate the elongated brush support member prior toremoval of this element from the sensing unit. Referring to this figure,there is shown a sensing brush assembly 81 which includes a generallyrectangular, elongated rod or brush support bar member 84 of insulatingmaterial which is fixedly attached to the sensing brush assembly 81 byconventional means which may include a metal supporting member orbracket 91 at opposite ends, each having an upwardly directed end orflange 92 which is secured by means of suitable screws 93. Instead ofusing a pair of oppositely disposed brush elements positioned on eitherside of the bar 84 in the manner of the preferred embodiment, there isprovided an obliquely positioned single brush element 82 which includesa downwardly directed flexible portion 94 having a beveled tip 95 whichmakes contact with the hot roll 80. In similar manner to the preferredembodiment, each brush element 82 is secured within a suitabletransverse slot 86 of bar 84 by means of a slotted screw'bolt 87. Theopposite upwardly disposed end of the brush element 82, rather thanbeing flexible, may be relatively rigid and is adapted to contact aconductive surface 96 formed on the printed circuit board 83 rigidlysecured to a suitable support member 97. A flexible wire lead 88 may beconnected to the printed wire circuitry 96 of board 83 by suitableelectrical connector means 89. In order to provide some flexibility tothe contact arrangement between the brush element 82 and the conductivesurface portion 96 of printed circuit board 83, there is provided behindthe portion 96 a flexible spring stop member 98 which has an outwardlycurved terminal portion 99 giving a desired degree of resilience to theterminal portion of the printed circuit element 83.

In this embodiment, instead of rotating the elongated brush supportmember prior to removal thereof, it is only necessary to releasesuitable clamps 90 by swinging the same aside and then lift the brushsupport member vertically out of its recess in the body 10.

In order that the brushes 82 will not be damaged, spring means are usedto cause the brush assembly 81 to pop-up when clamps 90 are released. Atopposite ends, in a recess in the bottom of the body A, bolts 102threaded into the brush assembly 81 pass through a bottom plate 103(FIGS. 10 and 12) and are surrounded by springs 104 which seat insuitable recesses in plate 103 and exert raising pressure on the bottomof sensing brush assembly 81 to give the latter a floating or yieldableelfect. The bottom plate 103 has a longitudinal opening 107 into whichthe lower ends 95 of the brushes 82 are lifted when the clamps 90 arereleased so that after the brush holder or assembly is lifted out of thebody it can be set down on a work bench or other surface without damageto the brushes.

While there have been shown and described and pointed out thefundamental novel features of the invention as applied to preferredembodiments, it will be understood that various omissions andsubstitutions and changes in the form and details of the deviceillustrated and in its operation may be made by those skilled in theart, without departing from the spirit of the invention. It is theintention, therefore, to be limited only as indicated by the scope ofthe claims.

What is claimed is:

1. A card sensing unit comprising an elongated conductive memberconnected to a source of electrical potential and adapted to support amoving card; a printed circuit board carrying a plurality of spaced,insulated, stationary contacts positioned adjacent said elongatedconductive member; an elongated brush support member adapted to bepositioned intermediate said elongated conductive member and saidprinted circuit board; a plurality of individual, spaced, insulated,conductive brush elements mounted on opposing sides of said brushsupport member at right angles to the axis thereof with their free endsextending away from said brush support member in opposite directions;means for electrically connecting said aligned conductive elements onsaid brush support member; means for rotatably mounting said brushsupport member between said elongated conductive member and said printedcircuit board whereby said oppositely positioned, individually aligned,conductive elements on said support member can be moved into and out ofcontact with said elongated conductive member and associated contacts onsaid printed circuit board to facilitate removal of said brush supportmember from said unit; and further including a hand wheel positioned forrotation adjacent said rotatably mounted brush support member, gearmeans interconnecting said hand wheel and said brush support member andmeans for preventing rotation of said hand wheel when said conductivebrush elements on said support member are moved into contact with saidelongated conductive member and the associated contacts on said printedcircuit board. 1

2. A card sensing unit comprising an elongated conductive memberconnected to a source of electrical potential and adapted to support amoving card; a printed circuit board carrying a plurality of spaced,insulated, stationary contacts positioned adjacent said elongatedconductive member; an elongated brush support member adapted to bepositioned intermediate said elongated conductive member and saidprinted circuit board; a plurality of individual, spaced, insulated,conductive brush elements mounted on opposing sides of said brushsupport member at right angles to the axis thereof with their free endsextending away from said brush support member in opposite directions;means for electrically connecting said aligned conductive elements onsaid brush support member; and means for rotatably mounting said brushsupport member between said elongated conductive member and said printedcircuit board whereby said oppositely positioned, individually aligned,conductive elements on said support member can be moved into and out ofcontact of said elongated conductive member and associated contacts onsaid printed circuit board to facilitate removal of said brush supportmember from said unit; and, wherein said means for rotatably mountingsaid brush support member include a first shaft fixed to said brushsupport member, a second shaft, means for mounting said second shaft forlimited axial movement between two positions, gear means interconnectingsaid first and second shaft, positive locking means on said second shaftadapted to prevent rotation of said second shaft in one axial positionand adapted to allow free rotation of said shaft in said other axialposition, and means for biasing said shaft to said first axial positionwhereby said brush support member is prevented from rotation except uponaxial shifting of said second shaft.

3. A card sensing unit comprising an elongated conductive memberconnected to a source of electrical potential and adapted to support amoving card; a printed circuit board carrying a plurality of spaced,insulated, stationary contacts positioned adjacent said elongatedconductive member; an elongated brush support member adapted to bepositioned intermediate said elongated conductive member and saidprinted circuit board; a plurality of individual, spaced, insulated,conductive brush elements mounted on opposing sides of said brushsupport member at right angles to the axis thereof with their free endsextending away from said brush support member in opposite directions;means for electrically connecting said aligned conductive elements onsaid brush support member; and means for rotatably mounting said brushsupport member between said elongated conductive member and said printedcircuit board whereby said oppositely positioned, individually aligned,conductive elements on said support member can be moved into and out ofcontact with said elongated conductive member and associated contacts onsaid printed circuit board to facilitate removal of said brush supportmember from .said unit; and, wherein said means for rotatably mountingsaid elongated support member includes a first shaft rigidly coupled tosaid brush support member and adapted to be freely rotatable within saidsensing unit, a second shaft having its axis extending parallel to saidfirst shaft, gear means interconnecting said two shafts, support meansfor said second shaft allowing free rotation and limited axial movement,a pin extending axially of said second shaft, stationary means includinga cooperating aperture positioned in the path of said axially movingpin, means for biasing said second shaft in an axial position such thatsaid axially moving pin protrudes within said aperture whereby saidbrush support member is prevented fro-m rotating when said alignedconductive elements are in contact with said elongated conductive membetand the associated contacts on said printed circuit board.

4. A card sensing unit comprising an elongated conductive memberconnected to a source of electrical potential and acting to support amoving card, a printed circuit board stationarily positioned adjacentsaid elongated conductive member and carrying a plurality of spaced,insulated, stationary conductive portions, an elongated insulating brushsupport member, a plurality of individual, spaced, conductive brushelements mounted on opposing sides of said elongated support member atright angles to the axis thereof with their free ends extending awayfrom said support member in opposite directions, means for electricallyconnecting aligned opposed conductive elements on said support member,stationary support means for mounting said elongated brush supportmember between said elongated conductive member and said stationaryprinted circuit conductive portion, means for rotating said elongatedbrush support member on said mounting means whereby said free ends ofsaid oppositely positioned brush elements on said support member may bemoved into and out of contact with said elongated cylindrical conductivemember and associated conductive portions of said printed circuit board,and means allowing said elongated brush support member to be slidaxially away from said unit on an axis generally parallel to the axis ofsaid elongated conductive member after said brush elements have beenrotated from a contacting position to a noncontacting position so thatsaid brush support member may be easily removed from said unit.

5. A card sensing unit comprising an elongated conductive memberconnected to a source of electrical potential and adapted to support amoving card, a printed circuit board carrying a plurality of spaced,insulated stationary contacts positioned adjacent said elongatedconductive member, an elongated insulative brush support member having acruciform cross sectional configuration, a plurality of spaced, alignedbrush receiving slots formed on opposite faces of said brush supportmember at right angles to the axis thereof, a plurality of conductivebrush elements positioned within said slots, means for rigidly securingsaid brush elements within said slots and electrically connectingoppositely aligned brush elements, said brush elements includingflexible free ends extending away from said support member in oppositedirections, stationary support means for supporting said elongated brushsupport member between said elongated conductive member and said printedcircuit board with individual brush elements aligned with associatedconductive portions on said printed circuit board and means for allowinglimited rotation of said elongated support member on said support meanswhereby said oppositely positioned, individually aligned conductiveelements on said support member may be moved into and out of contactwith said elongated conductive member and said associated stationarycontacts of said printed circuit board to facilitate removal of saidbrush support member from said unit.

6. A brush support member for a card sensing unit including an elongatedconductive member connected to a source of electrical potential andadapted to support a moving card and a printed circuit board carrying aplurality of spaced, insulated, stationary contacts posi-; tionedadjacent said elongated conductive member, said I brush support memberadapted to be positioned intermediate said elongated conductive memberand said:

printed circuit board for completing desired electrical circuits, saidbrush support member comprising a pair of oppositely disposed faceportions having a plurality of spaced slots positioned generallytransverse to the longitudinal axis of said brush support member,individual elongated conductive brush elements adapted to be positionedwithin said slot having free ends extending therefrom in one directionalong one face portion and in another direction along another faceportion, said brush support member having threaded bolt receivingapertures extending through said member at right angles to said spacedslots, a cooperating conductive mounting bolt positioned in each of saidthreaded apertures, said mounting bolts each having a pair of transverseapertures formed therewithin and acting to respectively receive apair ofsaid conductive brush elements when positioned in said slots wherebyrotational movement of said mounting bolts within said bolt receivingapertures acts to secure said pair of individual brush elements withintheir respective slots allowing individual adjustment.

7. Apparatus as claimed in claim 6 wherein said brush support memberincludes a plurality of aligned slots on opposing faces of said brushsupport member to receive two duplicate sets of brush elements and saidconductive mounting bolt includes a pair of apertures formed Within saidbolt near the inner and outer extremities thereof, said bolts positionedwithin said bolt receiving apertures and said brush elements positionedwithin said slots and extending through respective apertures in saidbolts to securely position in electrically conductive relationship apair of brush elements within their respective slots.

8. A removable brush support assembly for a card sensing unit includingan elongated conductive member connected to a source of electricalpotential and adapted.

to support a moving card, and a printed circuit board carrying aplurality of spaced, insulated, stationary contacts positioned adjacentsaid elongated conductive member, said brush support assembly includingan elongated insulative support member having a plurality of spaced,conductive brush elements positioned on opposing sides of said supportmember with the brush elements including free ends extending away fromsaid support member in opposite directions, means for electricallyconnecting said conductive brush elements, stationary support means forsupporting said brush support assembly between said elongated conductivemember and said printed circuit board while allowing longitudinalremoval thereof, said brush support assembly further including means forrotatably mounting said elongated brush support member, a pair of brushprotective members positioned on either side of said brush supportassembly and extending longitudinally thereof, said brush protectivemembers having an elongated, longitudinally extending, central slot,through which the free ends of said brush elements extend, and means forrotating said brush support member within said brush support assemblywhereby the free ends of said brush elements move from a protectedposition within said slots to a position in which the free ends extendaway from said brush assembly exterior of said slot, thus protecting thebrush support assembly during removal of said brush support assemblyfrom said stationary support means. I

9. Apparatus as claimed in claim 8 including detent means mounted onsaid brush support member and adapted to prevent longitudinal removal ofsaid brush support assembly when said brush support member is rotated toa p ti n where the free ends of said conductive brush elements extendexteriorly of the slot of said brush protective members.

10. A card sensing unit comprising an elongated, conductive memberconnected to a source of electrical potential and acting to support amoving card, a printed circuit board stationarily positioned adjacentsaid elongated conductive member and carrying a plurality of spaced,insulated, stationary conductive portions, an elongated brush supportassembly, means allowing said assembly to be longitudinally slid intoposition between said elongated conductive member and said printedcircuit board, said assembly including an elongated brush support memberrotatably mounted on said assembly and carrying a plurality ofindividual, spaced, conductive elements on opposed surfaces of saidsupport member, said conductive brush elements being mounted on saidsupport member at generally right angles to the axis thereof with theirfree ends extending away from said support member in oppositedirections, a pair of stationary brush protective plate elements,positioned on opposite sides of said rotatable brush support member,said protective plate members including central, longitudinallyextending apertures acting to protectively receive said brush elementswhen said brush support member is in a first position, and acting toallow said brush elements to extend through said apertures when saidbrush support member is rotated to a second position enabling the freeends of said oppositely positioned brush elements to move into contactwith said elongated conductive member and associated conductive portionsof said printed circuit board while allowing said brush support assemblyto be slid axially of said unit on an axis generally parallel to theaxis of said conductive member after the brush elements have beenrotated to a noncontacting position thus facilitating removal of saidbrush support assembly from said unit.

11. Apparatus as claimed in claim 10 further including detent meanspositioned on said elongated brush support member extending away fromthe axis thereof and acting to contact a portion of said card sensingunit to prevent axial movement of said brush support assembly withrespect to said card sensing unit when said brush support member is insaid second position.

12. A card sensing unit comprising an elongated conductive memberconnectable to a source of electrical potential and adapted to Support amoving card, a printed 1Q circuit contact board carrying a plurality ofspaced, insulated, stationary contacts spaced from said elongatedconductive member, a brush support assembly including a plurality ofindividual, cooperating spaced conductive brush elements, and means forsupporting said brush support assembly for movement with respect to saidelongated conductive member and said printed circuit contact boardwhereby individual electric circuits can be completed from saidconductive member to associated printed circuit board contacts with saidbrush support assembly being readily removable from said unit, saidbrush support assembly including two oppositely disposed face portionshaving a plurality of spaced slots positioned generally transverse tothe longitudinal axis of said brush support assembly, said individualconductive brush ele ments being adapted to be positioned within saidslots having free ends extending therefrom in one direction along oneface portion and in another direction along the other face portion, abrush member having threaded bolt receiving apertures extending throughsaid member at right angles to said spaced slots, a cooperating mountingbolt positioned in each of said threaded apertures, said mounting boltseach having a pair of transverse apertures formed within said boltmember and acting to receive said conductive brush elements whenpositioned in said slots whereby rotational movement of said mountingbolts within said bolt receiving apertures acts to secure a pair of saidindividual brush elements within their respective slots allowingindividual adjustment.

References Cited by the Examiner UNITED STATES PATENTS 1,839,398 1/1932Lee 23561.11 2,395,557 2/1946 Leathers 23561.11 2,543,906 3/1951 Ford200-46 2,615,626 10/1952 Luhn 235-61.11 2,615,627 10/1952 Stuivenberg 23561.11 2,829,831 4/1958 Stewart 23561.11 2,833,473 5/1958 Engel 23561.113,014,654 12/1961 Wilser 23561.11 3,015,004 12/1961 Fowle 20046 MALCOLMA. MORRISON, Primary Examiner.

WALTER W. BURNS, JR., Examiner.

4. A CARD SENSING UNIT COMPRISING AN ELONGATED CONDUCTIVE MEMBERCONNECTED TO A SOURCE OF ELECTRICAL POTENTIAL AND ACTING TO SUPPORT AMOVING CARD, A PRINTED CIRCUIT BOARD STATIONARILY POSITIONED ADJACENTSAID ELONGATED CONDUCTIVE MEMBER AND CARRYING A PLURALITY OF SPACED,INSULATED, STATIONARY CONDUCTIVE PORTIONS, AN ELONGATED INSULATING BRUSHSUPPORT MEMBER, A PLURALITY OF INDIVIDUAL, SPACED, CONDUCTIVE BRUSHELEMENTS MOUNTED ON OPPOSING SIDES OF SAID ELONGATED SUPPORT MEMBER ATRIGHT ANGLES TO THE AXIS THEREOF WITH THEIR FREE ENDS EXTENDING AWAYFROM SAID SUPPORT MEMBER IN OPPOSITE DIRECTIONS, MEANS FOR ELECTRICALLYCONNECTING ALIGNED OPPOSED CONDUCTIVE ELEMENTS ON SAID SUPPORT MEMBER,STATIONARY SUPPORT MEANS FOR MOUNTING SAID ELONGATED BRUSH SUPPORTMEMBER BETWEEN SAID ELONGATED CONDUCTIVE MEMBER AND SAID STATIONARYPRINTED CIRCUIT CONDUCTIVE PORTION, MEANS FOR ROTATING SAID ELONGATEDBRUSH SUPPORT MEMBER ON SAID MOUNTING MEANS WHEREBY SAID FREE ENDS OFSAID OPPOSITELY POSITIONED BRUSH ELEMENTS ON SAID SUPPORT MEMBER MAY BEMOVED INTO AND OUT OF CONTACT WITH SAID ELONGATED CYLINDRICAL CONDUCTIVEMEMBER AND ASSOCIATED CONDICTIVE PORTIONS OF SAID PRINTED CIRCUIT BOARD,AND MEANS ALLOWING SAID ELONGATED BRUSH SUPPORT MEMBER TO BE SLIDAXIALLY AWAY FROM SAID UNIT ON AN AXIS GENERALLY PARALLEL TO THE AXIS OFSAID ELONGATED CONDUCTIVE MEMBER AFTER SAID BRUSH ELEMENTS HAVE BEENROTATED FROM A CONTACTING POSITION TO A NONCONTACTING POSITION SO THATSAID BRUSH SUPPORT MEMBER MAY BE EASSILY REMOVED FROM SAID UNIT.